Reuters: "This is not air — this is a horror," says Natalya Maksymenko, a 25-year-old mother, screwing up her nose at the smoke belching out of factory chimneys in Dniprodzerzhynsk. Dirt-encrusted shop fronts stretch out along Lenin Avenue in the industrial city of 250,000 people, birthplace of Soviet leader Leonid Brezhnev. They end in a haze at a gigantic steel complex surrounded by swirling fumes. Ukraine has halved carbon dioxide output from 1990 levels to 345 million tonnes a …